Railroad and train systems vary drastically in the speeds at which they operate, and the times and distances needed to stop. Additionally, as a result of terrain and space considerations trains often share tracks. In particular, for bi-directional shared lengths of track, electromechanical warning indication systems are located proximate track switches, which are utilized to provide a warning to trains approaching the switch that the upcoming track is presently occupied. These warning indication systems function similarly to a stoplight at a road intersection, wherein the indication system provides some indication that it is not presently safe to proceed. Typical warning indication systems utilize a visual stimulus, in the form of a red annunciator lamp, in order to signal to the train operator of the upcoming tracks status. The train operator is then relied upon to take appropriate action in order to bring the train to a stop prior to passing the annunciator lamp, thus averting a collision with a second train occupying the track ahead.
Unfortunately, many train collisions and derailments can be attributed to human error, namely an operator's failure to bring the train to a stop prior to passing the annunciator lamp. Such incidents are commonly referred to as run-through-red incidents. Run-through-red incidents can occur for a variety of reasons. In some example instances, the operator cannot be paying adequate attention, or can otherwise be incapacitated and either does not notice the warning in time, ignores the warning, or has become unable to take appropriate action in response to the warning.
The warning indication systems and the annunciator lamps rarely fail, as they often rely on a variety of sensors which indicate the presence of a train on a particular length of track. Additionally, these warning indication systems have various backup systems which account for power outages, sensor failures, or burnt out bulbs. These various safeguards ensure that at least some indicia regarding the warning is provided to the train operator. As such, collisions which occur on trains are typically caused by human failure in recognizing the warning and taking appropriate action to bring the train to a stop, and are not due to failure of the present warning indication systems.